During the times of terrorism and war, various guided and unguided missiles have been used resulting in casualties. A system that protects structures, ground/air/sea vehicles, and the people inside them against missile attack could save the lives of military troops as well as civilians. A common unguided missile currently used is the rocket-propelled-grenade (RPG). RPGs can come in both a single and tandem warhead form. The tandem warhead has two or more stages of detonation, namely a first stage detonation designed to trigger a reactive defense and a second stage detonation designed to attack the same location as the first stage detonation location. Tandem warheads generally are much larger and more lethal than single warheads, making predetonation alone a less attractive defense strategy. Also due to different fuzing methods at the different stages, short circuiting via impact of tandem warheads may not be achievable.
Existing technologies for RPG or missile defeat systems include application of slat armor to the military vehicles. The principle of slat armor is to stop the missile before it strikes the body of the target, to crush the missile and short circuit its electric fuze, or to cause shaped charge detonation at a standoff distance, rather than directly on the body of the vehicle. Disadvantages to slat armor are that it adds significant weight to the vehicle, and sacrifices maneuverability. The standoff distance it provides in case of predetonation is too short to be of significant benefit. Other RPG or missile defeat systems launch a single or small number of projectiles toward the incoming missile. These systems require accurate sensing of the missile trajectory, accurate aim of the projectiles in order to intercept the missile, and fast reaction time to slew and fire the projectile.
Another existing strategy for RPG defeat is to deploy a commercial air bag to trap and/or crush the RPG before it strikes the vehicle. Still another is to deploy a net-shaped trap made of super high strength ballistic fiber. Both the bag and the net are claimed to defeat the RPG by crushing its ogive and rendering the fuze inoperable. Both the airbag and the net intercept the RPG at a standoff distance of up to two meters. At this standoff distance, the RPG shaped charge jet still has significant penetrating ability. Neither of these competing technologies prevents the detonation of the RPG by its built-in self-destruct mechanism, nor do they protect nearby personnel from shrapnel from the exploding RPG.